1. Field of the Invention
The present invention relates to a push handle switch lampholder, and more particularly to the push handle switch lampholder that pushes a lower conductive plate to move like a see-saw by pushing a push handle to move back and forth and determines whether or not to pass a current to an upper conductive plate, so as to control the ON or Off of a light emitting element.
2. Description of the Related Art
As light bulb was introduced in 1879, it becomes a necessary illumination device for our life. In the use of the light bulb, a lampholder must be installed to act as a support and supply electric power, so that the lampholder is an important item for the use of the light bulb. In general, a conventional lampholder is operated by pressing a switch, and the lampholder is mainly divided into four types including a switchless lampholder (wherein the switch is installed on a power supply line), a knob switch lampholder, a zipper switch lampholder and a push handle switch lampholder.
With reference to FIG. 1 for a conventional push handle switch lampholder 1, the push handle switch lampholder 1 comprises a cylindrical shell 11, an insulating plate 12, an insulating base 13 and a push handle switch 14, wherein the cylindrical shell 11 is made of a conductive plate into a substantially cylindrical shape and having a threaded mouth for screwing and connecting a light emitting element such as a light bulb (not shown in the figure), and a first electrode of the light emitting element is contacted with cylindrical shell 11 to electrically couple to a negative electrode of the power supply such as a utility power supply (not shown in the figure), and the second electrode of the light emitting element is electrically turned to an ON position by the switch 14 to electrically couple to a positive electrode of the power supply, so as to emit lights by the circuit conduction. However, if the switch 14 is switched to an OFF position, the light emitting element will be turned off. The insulating plate 12 is installed at the bottom of the cylindrical shell 11, and a connecting groove 120 is formed thereon.
The insulating base 13 is installed under the insulating plate 12 and includes a containing groove 130 concavely formed on the insulating base 13 for embedding a negative electrode plate 131 and a positive electrode plate 132, and an end of the negative electrode plate 131 is extended to the top of the insulating base 13 and abutted against the bottom of the insulating plate 12, and the cylindrical shell 11, the insulating plate 12, the negative electrode plate 131 and the insulating base 13 are pivotally coupled, so that the negative electrode plate 131 and the cylindrical shell 11 are electrically connected, and the other end of the negative electrode plate 131 is connected to an exposed end of the power supply line, such that the negative power supply can be connected to the light emitting element. The positive electrode plate 132 includes a lower conductive plate 132a, at least two trigger plates 132b and an upper conductive plate 132c, and the lower conductive plate 132a is embedded into the insulating base 131. Since the exposed end of the power supply line is electrically coupled to the positive power supply, the trigger plates 132b are contained in both sides of the containing groove 130 respectively, and one of the trigger plate 132b proximate to the lower conductive plate 132a is electrically coupled to the lower conductive plate 132a, and the other trigger plate 132b is electrically coupled to the upper conductive plate 132c, and the upper conductive plate 132c is passed out of the connecting groove 120 and contacted with the second electrode of the light emitting element.
The switch 14 includes a push handle 141, a spring 142 and a metal plate 143, and the push handle 141 has a shape matched with the containing groove 130 for performing a pushing action reciprocally in the containing groove 130, and a middle section of the push handle 141 is hooked to an end of the spring 142. The metal plate 143 is substantially C-shaped, and an internal edge of the lower section is latched to the middle section of the push handle 141, and an internal edge of the upper section is hooked to the other end of the spring 142, so that when the push handle is pushed, the push handle is driven by an elastic force of the spring 142 to tilt towards one of the ends of the push handle 141. In FIG. 2, when the metal plate 143 is tilted towards an end of the push handle 141, the metal plate 143 is contacted with the trigger plates 132b on both sides respectively, so that the light emitting element is electrically connected to the positive power supply to emit light. However, when a user pushes the push handle 141 to move and drive the spring 142 to link the metal plate 143 to tilt towards the other end of the push handle 141, and the metal plate 143 will be separated from the contact of the trigger plates 132b on both sides, so that the light emitting element is turned off. By pushing the push handle 141 reciprocally, the user can control the circuit connection between the lampholder 1 and the light emitting element to be turned ON or OFF.
Although the aforementioned conventional push handle switch lampholder 1 is a common daily item, its manufacture and usage still have the following drawbacks:
(1) Difficult Assembly: Since the lampholder 1 uses a number of conductive plates for conducting current to the light emitting element, therefore the overall assembling operation is complicated and tedious, and the position may be shift easily by an external force to affect the effect of the lampholder 1, so that the convention lampholder 1 incurs a high manufacturing cost and many manufacturing issues.(2) Large Volume: Since the whole switch 14 must be accommodated into the containing groove 130, therefore the insulating base 13 is limited and its volume cannot be reduced effectively. As a result, the cost for the injection molding process of the insulating base 13 is high, and the large volume will also affect the warehouse storage and transportation costs.(3) Unsmooth Pushing Operation: When a user pushes the push handle 141, a force greater than the elastic force of the spring must be applied to the push handle 141 before the metal plate 143 is driven to contact with or separate from the positive electrode plates 132 on both sides. If the elastic force of the spring 142 is too large, then the user has to push the push handle 141 inconveniently. If the elastic force of the spring 142 is too small, then the push handle 141 will be too loose to cause a wrong movement. In addition, the spring 142 may become elastically fatigue after a long time of use, so as to affect the operation and effect of the lampholder 1.(4) Short Service Life: Since the metal plate 14 and the trigger plate 132b are contacted to allow a current flow, and the contact position is a point or a line, the metal plate 143 produces a high temperature and becomes deteriorated or broken after a long time of use, so as to shorten the service life of the lampholder 1.